Measured service telephone system



May 17, 1932. .1. EfosTLlNE MEASURED SERVICE TELEPHONE SYSTEM Filed Aug. 23, 1930 5 Sheets-Sheet l H11-H. l

May 17, 1932 J. E. OSTLINE 1,858,863

MEASURED SERVICE TELEPHONE SYSTEM Filed Aug. 23, 1930 s sheets-sheet 2 amsrsn BATTERY ausY wus Sept. 13, 1949. E. R. owl-:NS

2,481,863 PHOTOELECTRIC APPARATUS FOR DETECTING SURFACE DEFECTS IN GLASSWARE Filed April 26, 1945 3 Sheets-Sheet 5 Patented May 17, 1932 (UNITED STATES PATENT lOFI-flor.:

JOHN E. OSTLINE, lOlie" BERWYN, ILLINOIS, ASSIGNOB, BY MESNE ASSIGNMENTS, TO ASSOCIATED ELECTRIC LABORATORIES, INC., OF CHICAGO, ILLINOIS, A, CORPORATION OF DELAWARE MEASUBED SERVICE TELEPHONE svsm Application mea Augiilt 28,1930. semi No. 477.888.

`The present invention relates to measured service telephone systems in general, but is concerned more particularly with measured service telephone systems in which calls are extended by automatic switches; and the principal object, briefly stated, is the provision of new and improved circuit arrangements for such systems in which the subscribers are given a choice of several classes of metered service.

An individual subscriber may choose any one of the following three dierent classesv 'a monthly rate which entitles him to free calls within the main or local zone as well as to either the north or south zones and for calls into zones not covered by the free call arrangement, he pays on the basis of a fixed rate for each period of five minutes or raction thereof.

Another object of the invention is to provide a measured service. system for party line subscribers in which the party line subscribers receive class (B) metered service; that is, .the subscribers pay a flat rate which will entitle them to free calls within the main or local zone and a fixed rate on a time y basis on all calls to the north and south ment at the exchange regardless of the class of metered service furnished to each line.

One of the features of the present invention relates to the means whereby if a calling subscriber dials before he receives dial o tone, and therefore before a common meter Both party r control equipment is selected, the subscriber 1s vena busy tone.

ther objects, not yspecifically mentioned here will best be understoodby reading the letalled description and claims which fol- The drawings comprising Figs. 1-4, nclusive, arranged with Fig. 2 to the ri ht of Fig. 1 and Fig. 3 below Fig. 2 show su cient circuit details to enable the invention to. be described and understood.

there.. is shown at the left-hand side of the drawings two subscribers lines, the upper line` being Ia party line including vtwo substation circuits S and S and the lower line Referring now to Fig. 1 in more detail,

being an individual line with the substation circuit S2. The substation circuits S and S2 are identical, while in the substation S the shunt springs SS of the calling device have been modified 'somewhat and Will be more fully -described later. Both lines terminate in similar line equipment comprising the usual line and cut-0E relays, connector and' finder banks. A meter relay is associated with each line for controlling the operation of the subscribers meters, such as 28, 29, 28 and 31. The Vmeter 28 is individual to sub-l scriber S and the meter 29 is individual to subscriber S. The meters 31 and 28 are individual to subscriber S2; These and other similar subscribers lines are accessible to a group of line finders, one of which. is-

schematically shown Vto the right of the line and cut-off relays. v

This line finder is somewhat similar to the line finder disclosed in Patent No. 1,851,132, issued to N. H. Saunders.

In Fig. 2 is shown the selector repeater SR which is permanently connected to the line finder shown in Fig. 1. This selector repeater is somewhat similar to the selector repeater shown in Patent No. 1,332,217, issued March 2, 1920, to Emil Jacobsen, but the circuits have been modilied somewhat in accordance with the present invention. Associated with each selector repeater is a class minor switch CMS having w1pers'280 and 281 which are advanced step-by-step by the rotary magnet 284 and returned to normal position by release magnet 283. A time switch TS, similar` in construction to the control minor switch CMS, is also associated with each selector repeater. At the lower part of Fig. 2 there is shown the common conductors 43 to 47, inclusive, which extend from the lower banks of the class minor switches to the contacts of the meter relays. This group of conductors as well as conductors 301 to 4306, 11iclusive, are common to this particular group of finder-selector-repeater links.

In the upper-right-hand corner of Fig. 3 there is shown the classification switch finder CSF which is also individual to the selector repeater SR.`\The finder CSF is mechanically similar to the well known rotary lineswitch which advances its wipers step-bystep and which wipers have no normal posi` tion. At MIR there is shown one-of a group of meter impulse relays. This grou of rela s is individual to this group o finderselector-repeater links and are controlled lg a constantly rotating im ulse distributor I which is common to all t e groups of finderselector-repeater links in the exchange.

The wipers of the finder CSIj1 have access to a group of classification switches one'of which is shown at CS. The classlfication switch CS is of the well known Strowgerl vertical and rotary type of switch. Associated with each classification switch is a rotary control switch, such as RCS which is similar in construction to the well known rotary 11neswitch. Dependent upon the class of metering service to be provided for each particular exchange in the telephone area, certain contacts in the bank of the classification switch CS are jumpered and connected to certain bank contacts of the rotary control switch R S.

(liig. 4 shows a detailed view of the shunt spring combination of the calling device of substation S.

General operation When -the calling subscriber initiates a call, the subscribers line relay is energized to initiate the operation of the finder which hunts for and finds the calling line. As soon as the finder finds the calling line the classification finder CSF associated -with the finder-selector-repeater link hunts for an idle classification switch and when this is found the calling subscriber is given the well known dial tone.

In case the subscriber should dial before the receipt of dial tone, the selector repeater is operated to the level dialled and is automatically rotated to its eleventh position from where the busy tone is given to the subscriber.

Assuming that the subscriber waits for dial tone and on receipt thereof dials the first digit of the desired number to step the selector repeater to the required level from which point the selector will rotate and select an idle second selector. At the same time that the impulses for operating the selector repeater were sent, pulses were also beine delivered by way of the classification finder CSF to operate the selected classification switch CS.

After the first digit the selector-repeater SR rotates its Wipers to select an idle second selector and the rotary control switch RCS advances one step to transfer the impulsing circuit from the vertical magnet to the rotary et of classification switch CS.

es onsive to the calling subscriber dialling t e second digit of the desired number the selector repeater repeats these impulses to the second selector and to the rotary magnet of the classification switch. The classification switch rotates its wiper in accordance with this digit and grounds a particular Contact in its ba r. After the second digit the rotary control switch RCS advances to third lposition from where it is automatically operated stepby-step by relay 385 which is now connected to a common pulsing lead. The class minor switch CMS is operated by relay 385 in unison with the rotary control switch.

The step-by-step operation of the class minor switch and the rotary control switch continues until the wiper 364 of the rotary control switch connects with a contact in its bank which is connected to the `grounded contact in classification switch bank. When this contact is reached, both the class minorswitch CMS and the rotary control switch RCS stop. The class minor switch CMS is held in this position to control the metering when the called party answers, while the classification switch CS and rotary control switch RCS return to normal for use in other calls.

Depending on the class of metering to be produced when any particular office or digits are dialled, the classification switch bank is jumpered to the bank contacts accessible to wiper 364 of the rotar control switch RCS.

When the called su .scriber answers a relay operation takes place which operates the calling subscribers meter relay and an impulse is sent over one of common metering leads to operate the subscribers meter in accordance with the setting of the class minor switch. In this case since the called subscriber is in the same zone and the calling subscriber pays for every such call on a metered basis the class minor switch is in position one. A single impulse is then sent over lead 43 to operate the calling subscribers meter at the time the meter relay is in operated position. Thev calling subscribers meter is therefore operated once for this type of call.

At this time it should be pointed out that for the different classes of metered service provided there will be another meter connected to this particular subscribers meter relay. This meter has two windings and will be connected to leads 49 and 51 in order to charge for calls into the north land south zones.

Assuming that the calling subscriber dialled a number in the north zone instead of the local zone the operations are the same as just described with the exception that the classification switch is operated to ground a contact which is connected to another bank contact in the rotary control switch RCS. The rotary control switch and the class minor switch are therefore again stepped in unison and the class minor switch CMS is stopped in second position when. the rotary control switch RCS finds the grounded contact.

When the called party answers on this call the relay operation again takes place in response to the timed pulse arrangement to operate the meter relay and the subscribers meter, this time over lead 44 since the call was tothe north zone. Since the class minor switch is now in position two the time switch TS is operated step-by-step for the duration of the call to first apply a warning tone to the calling line and to operate the meter another step in case the calling subscriber continues t0 maintain the connection. The meter is therefore operated once when the called partyanswers and once for every predetermined time interval thereafter depending on the length of the conversation. In case the .call was to the south zone the classification switch CS, the rotary control switch RCS and the class minor switch CMS would be stepped to corresponding positions and when the called subscriber answers the relay operation and metering would take place similar to the north Zone, this time, however, the metering would be over lead 46.

From the above brief description it can readilyy be seen that the class of metered service as outlined under the classes B and C can easily be given in the case of class B by omitting the meter connected to leads 33 or 48 and connecting a double wound meter to leads 34 and 36 or leads 49 and 5l. In the case of servicc under class C the meter on lead 33 is omitted and a meter is connected to either lead 34 or 36 as the case may be.

As previously stated, metered party line service is furnished with this equipment but in this case the subscriber can only have the type of service underlined under class B, that is, he pays a monthly rate suicient to vinsure free calls in the main or local zone and pays for calls on the time basis to the north and south zones.

In the case of calls from the first party on pulses sent out after each digit have no particular significance, because only the first ground ulse is utilized to produce the desired e ect. After the second party subscriber has reached the first selector repeater and obtained the dial tone, he will sta-rt dialling in the usual manner. As soon as he turns his dial, however, a momentary ground pulse vwill be placed on the line and this will cause differential relay 203 to operate on account of one of its windings becoming shunted. The operation of rela 203 will cause the resistance 230 in the ho ding lead to the classification switch to be shunted out and this occurrence will cause marginal relay 384 in the classification switch to op-` sible to wiper 364 of the rotary control switch.

RCS will appearat diderent positions on accountof being switched by relay 384. Therefore, a call to north zone instead of causing the class minor switch CMS to stop in the second position will cause it to stop in the third position and a call to the south instead of causing the class minor switch to stop in the fourth position will cause it to stop in the fifth position. When the called subscriber answers, the same action will take place as previously described for a single subscriber having class B service. It will be noted, however, that the meter relay 30 will not operate except when ground pulses appear on either leads or 37, and consequently when ground is connected to the metei` pulse leads the meter connected thereto will operate. As will be noted the single and party line subscribers have identical line circuits and each line has a-meter relay. The meter leads extending to this relay will be connected to two meters one of which will register calls made by the first party and the second of which will register calls made by the second party. This two party metering group when the jack per-station system of wiring is used.

In the case of special service calls to special operators which, of course, should not be metered against the subscriber, the classification switch, in conjunction with the first selector-repeater is so arranged that metering will be prevented and the special service operator obtains a direct line to the subscriber with the first selector-repeater bridge removed. This service is particularly rethrough the lower winding of rela quired in conjunction with the present method of handlin toll calls on the so-called CLR or combined-line-and-recording basis, aswell as pay station services. On these types of calls the subscribers dial the special service code upon the selector-repeater and classication switch which in turn causes the class minor switch CMS to move to its sixth position. When the class minor switch reaches is sixth position the bridges at the selectorrepeater are removed in a manner to be more fully described hereinafter.

In the case of reverting calls on a party line, the code dialled is arranged to produce the same setting on the class minor switch CMS in order to remove the selector-repeater vbridge and to connect the calling line direct to the reverting call switches.

In the case of calls for the operator it is customary to dial only one digit, that is digit 0. This, of course, will not cause the classiication switch to step into the bank nor will it cause the control switch to go into third osition, because there is no second digit dial ed in. This condition, however, vis met by arranging normal post springs on the classification switch which operates on the tenth level and produces the same conditions as those produced by dialling two or three digits of the special service code. g

Having briefly described the apparatus and its functions a detailed description will now be given.

Line S2 initiates a @all Assume now that line S2 initiates a call, a circuit may be traced for energizing line relay 7 by way of ground through the upper winding of relay 7, armature 14, upper line conductor 5, through the substation circuit to lower conductor 6, armature 16,?,and

to battery. Line relay 7, upon energlzing, at armature 11 connects the cut-olf relay 8 to the test contacts in the line finder banks to apply negative battery otential to this contact to enable the line nder to cut through on the calling line and at 12 connects ground to the finder start lead 17 to initiate the operation of the line finder in a manner described in the aforementioned Saunders application or in a manner somewhat similar to Patent 1,688,588, issued to Lomax et al., on October 23, 1928. The line linder is operated step-by-step in its Vertical movement to find the group in which the calling line terminates and is then rotated step-by-step to find the calling line. When the test wiper 23 of the line finder encounters the negative battery potential applied through both resistance 13, and cut-off relay 8 by way of armature springs 11, the line nder will switch through and connect the subscribers line conductors 5 and 6 to the line conductors 25 and 27 extending to the selector-repeater shown in Fig. 2. The` cut-off relay 8 is energized from ground in`the line finder by way of test wiperl 23, amature 11 and through the winding of cut-olf relay 8', to battery. At armature 15 cut-ofi` relay 8 completes a locking circuit for itself and also connects ground to conductor 9 extendin to the connector banks to guard this line against seizure from the connector and at armatures 14 and 16 disconnects the line relay 7 from the subscribers line conductors. Line relay 7 deenergizes and at armature 11 opens the original energizing circuit at the cut-olf relay 8 and at armature 12 opens the finder start lead. As soon as the subscribers loop is extended to the selector-repeater, line relay 202 is energized over the following circuit: from ground by way of normally closed sprin s controlled lby armature 275, normally close springs controlled by vertical olf-normal springs 226, through the lower winding of dil'erential relay 203, the lower windin of relay 202, normally closed springs contro led by armature 220, normally closed springs controlled by armature 245, conductor 27, through the finder and subscribers loop back to conductor 25, normally closed springs controlled by armature 243, normally closed springs controlled by armature 219, through the upper winding of line rela 202, and through the upper winding of di erential relay 203 to battery. Diierential 203 does not energize over the above traced circuit because its upper and lower windings are in opposition. Line relay 202, lupon energizing, at armature 223 and its working contact energizes the repeating relay 205 over an obvious circuit. The energization of repeating relay 205 is without effect at this time. At armature 224 line relay 202 closes a circuit for slow-to-release relay 204 by way of grounded armature 244, armature 224 and its Working contact and through the winding of release relay 204, to battery. Release relay 204, upon energizing, at armature 227 grounds the release trunk conductor 26 by way of normally closed springs controlled by armature 254;

at armature 228 prepares the impulsing cir-- cuit to the classification switch CS; at armatures 229 and 231 prepares circuits for operating the finder switching relay 215 or the inder magnet 312 of the classification switch iinder CSF dependent upon whether the wipers of the finder are standing in engagement with an idle classification switch; and at armature 232 opens a point in the release circuit and prepares the impulsing circuit to the vertical magnet of the selector repeater.

Assuming now that the Wipers of the classiiication switch finder CSF are in engagement with a busy classification switch, guard wiper 316 will be in engagement with a contact having ground potential thereon with the result that this round potential extending by way of con uctor 310, armature 272 and its resting contact, armatureA 229, armature 239, to the lower termlnal of finder switching relay 215 will short-circuit this relay from ground extending from ounded armature 231 and armature 240. Witchlng relay 215, therefore, does not energize and the ground extending to the lower terminal of switching relay 215 may be traced by way of verticaloifnormal springs 274, conductor 307, interrupter sprin 313, and through the winding of the stepping magnet 312 to battery to energize the stepping magnet to rotate the wi ers of the finder to search for an idle classi cation switch. At interrupt'er springs 313\stepping magnet 312 intermittently interrupts 1ts` own circuit and steps the wipers in search of an idle classification swltch as long as the guard wiper 316 encounters ground potential on successive bank contacts of busy classification switches. When an idle classification switch is found guard wiper 316 no longer encounters a ground potential with the result that switching relay 215 is energized over the followmg circuit: from ground b way of armature 231, armature 240, winding of switchmg relay 315, vertical off-normal springs 274, conductor 307, interrupter springsA 313, and through the winding of stepping magnet 312 to battery. Switching relay 215 energizes over the above traced circuit, but due to the high resistance of the switching relay 215 the stepping magnet 312 is not energized. At armature 269 switching relay 215 removes one of the shunting grounds from around the selector-repeater switching relay 206; at armature 270 prepares an impulsing circuit to the classification switch CS; at armature 271 closes a circuit for relays 383 and 384; at armature 272 connects ground to the guard lead 310 to prevent any other selector-repeater from seizing the selected classification switch; at armature 273 closes a locking circuit for itself independent of the vertical off-normal springs 274 which open on the first vertical step of the selectorrepeater; at armature 276 prepares an impulsing circuit to the rotary magnet 284 of the class minor switch CMS; and at armature 275 connects grounded dial tone in place of ground through the lower windings of relays 203 and 202 and thence over the subscribers loop for transmitting the dial tone to the calling subscriber in the well known manner.

Responsive to the energization of the finder switching relay 215, relay 383 is energized over the following circuit: ground by way of armature 231, resistance 230, armature 271,

conductor 309, wiper 315, conductor 319, armature 372, winding of relay 383, and through the lower winding of relay 384 to battery. Only relay 383 energizes over the above traced circuit since the relay 384 is marginal and will not energize in series with the resistance 230. Atarmature 374 relay 383 o ens one point in the release circuit of the ciessifcation switch and at its workin contact connects round to the guard con uctor 320 with whic the guard wi er 316 is now in engagement. At armature 3 5 relay 383 prepares a locking circuit for two-,step relay 381 at-its working contact and at its resting contact opens the releasing circuit of the rotary control switch RCS.

When subscriber S2 hears the Well known dial tone the subscriber will dial the first digit of the desired number. Responsive thereto when the calling device or dial is moved in an off-normal position the shunt springs SS2 are operated to shunt the receiver and transmitter and when the dial is released the impulse springs IS2 opens the circuit 'extending to the line relay 202 to deenergize the line rela a number of times dependent upon the digit dialled. Responsive to each deenergization of line relay 202 a ground impulse is'transmitted by way of armature 223 and its resting contact, armature 228, armature 270, to impulse conductor 308. Each deenergization of the line relay 202 also transmits an impulse of current from ground by way of armature 244, armature 224 and lts resting con-tact, armature 232 and its working contact, through the winding of series relay 208 to battery, and through armature 242 and the winding of vertical magnet 216 to battery for energizing series relay 208 and Avertical magnet2l6. Release relay 204 being a sloW-to-release relay is maintained energized during the impulsing period even though its circuit is temporarily interrupted at armature 224. Series relay 208 is also a slow-to-release relay and therefore maintains its armatures in operated position during impulsing and at armature 246 closes a short-circuit around the upper windings of relays 210 and 211, and at armature 247 and its working contact closes another shunt circuit around the switching relay 206. This shunt circuit is placed around the switching relay 206 to prevent its energization when the vertical off-normal springs 249 are closed on the first vertical step of the selector-repeater. By the operation of the vertical magnet 216 the wipers of the selectorrepeater are stepped in a vertical direction responsive to each impulse received by the Vertical magnet. On the first vertical step the vertical off-normal springs of the selector-repeater are operated to close the following circuits: at Vertical oil-normal springs 226 direct ground is connected by way of the normally closed springs controlled by cam springs 221 to replace the grounded dial tone; vertical off-normal springs 233 prepares the circuit for 'the release magnet 217 of the selector-repeater; at vertical off' -normal springs 249 closes a circuit for energizingthe stepping relay 209; and at vertical off-normal springs 274 opens the original energizing circom letes a locking circuit for itself extending y-way of interrupter springs 235 of the rotary magnet 218. At armature 248l stepping relay 209 laces an obvious ground shunt circuit aroun switching relay 206; anduat armature 250 prepares a circuit for energlzing the rotary magnet 218. When series relay 208 deenergizes shortly after the -irst series of impulses, a circuit may be traced for operating the rotary magnet 218 as follows:

from ground by way of armature 227, normally closed springs controlled by armature 238, armature 247 and its resting contact, ar-

mature-250 and through the-winding of rotary magnet 218 to battery. Responsive to the energization of the rotary magnet 218 the wipers of the selector repeater are rotated into enga ement with the first set of bank contacts of tie selected level and at interrupter springs 235 rotary magnet 218 opens the locking circuit of stepping relay 209 which deenergizes. At armature 250 the deenergization of the stepping relay 209 opens the circui-t of the rotary magnet. The peration from now on is depende-nt upon whether the test wiper 27 8 encounters a grounded potential of a' busy second selectorvor not. v.Assuming now that the second selector terminating in this first set of contacts is busy the test wiper 278 will encounter a ground potential which will maintain the switching relay 206 shunted to prevent its energization. This busy ground potential closes a circuit for energizing the stepping relay 209 by way o f test wiper 27 8, armature 238 and its resting v contact, interrupter springs 235, off-normal springs 249, and through the winding of stepping relay 209, to battery. Stepping magnet 209 again energizes and again completes the locking circuit for itself as well as to again complete the circuit for energizing the rotary magnet 218, to cause the wipers of the selector-repeater to rotate to the next set of contacts. `The operation just described continues until thetest wiper 27 8 no longer encounters a busy ground potential or until the wipers are rotated beyond the last set of con R tacts, whereupon the cam springs 221 are opera-ted and the calling subscriber is given the busy tone in the well known manner.

` In case the next test contact encountered by test wiper 278 does not have a ground potential thereof, switching relay 206 will not be short-circuited with the result that the switching relay will energize over the following circuit: from ground by way 'of armature 227, winding of switching relay 206,

.interrupter springs 235, olf-normal s rings 249, an through the winding of steppmg relay 209 to batter Switching relay 206 energizes over the a ove traced clrcuit but stepping relay 209 bein marginal does not energize on account o the igh resistance of switching relay 206. At armature 236 switching relay 206 closes a loop circuit extending by way of wiper 277, armature 243 and its resting contact, armature 236, through the upper windings of relays 211 and 210, lower winding of repeating relay 205, normally closed springs controlled by armature 222, armature 234, resting contact of armature 245 and said armature, to wiper 279. The line relay of the'second selector is energized over the above tracedcircuit to prepare the second selec-tor for operation in the well known manner. At armature 238 and its working contact switching relay 206 connects grounded armature 227 to test wiper 278 to prevent any other selector repeater from Vseizing the selected second selector; at armature 240 opens the original energizing circuit of finder switchin relay 215; at armature 241 prepares a circuit relay 207; and at armature 242 opens the circuit extending to the vertical magnet 216. The circuit just traced through the upper windings of relays 210 and 211 causes the enor energizing the switching through armature 251 completes a circuit through the lower winding of electro-polarized relay 211 to prepare relay 211 for operation when the called subscriber answers and reverses battery through its upper winding. The circuit extending through the lower winding of repeating'relay 205 just traced is in opposition to the upper windin to cause a quick or slow deenerglzation of t 's relay in accordance with the length of line or resistance extending to the second selector while re eating impulses. The selector repeater R now re mains in this position until the next series of impulses are transmitted by the calling subscriber for operating the second selector.

Referring now to Fig. 3 and at a time when impulses were transmitted over conductor 308 by line relay 202, it will be seen that these impulses extend over wiper 314, conductor 318, series relay 356, vertical magnet 354 of the classification switch CS, conductor 395, wiper 363 of the rotary control switch RCS, and through resistance` 366, to battery. esponsive to this series of impulses the series relay 356 is maintained energized throughout the series of impulses while the vertical magnet 354 is operated for each impulse to step the wiper 358 of the classification switch opposite a certain level of contacts in accordance with the number of impulses received. On the first vertical step of the classification switch the vertical off-normal springs 351 and 352 are closed, the springs 351 to connect ground to the guard conductor 320 'and the springs 352 for preparing the release circuit for the release magnet 353 of the classlficatlon 5.' switch CS. Slow-to-release series relay 356,

upon energization, at armature 357 closes a circuit for energizing the ste pln magnet 368 of the rotary control switc R S to prepare the operating pawl to advance the rotary control switchiwhen the stepping magnet 368 is deenergize'd. Shortly after this series of impulses series, relay 356 at armature 357 opens the circuit of the steppmg magnet 368 with the result that the magnet deenergizes and advances the wipers 363 to 365, inclusive, of the rotary control switch from their first to their second positionsik Wiper 363 disconnects the vertical magnet 354 from the impulsing circuit and connects the rotary magnet 355 thereto.

The calling subscriber now dials the second digit of the desired number and the line relay 202 of theselector repeater is again intermittently operated in accordance with the number of impulses in the digit. At armature 224 series relay 208 is again energized during the impulsing period to shunt out the upper windings of relays 210 and 211 vat armature 246. At armature 223 line relay 202 transmits impulses to the repeating relay 205 and to impulse conductor 308. Upon each deenergization of line relay 202, impulse repeating relay 205 deenergizes and at armature 234 opens the loop circuit extending by way of ground through the lower winding of the line relay of the second selector, wiper 279, armature 245 and its resting contact, armature 234 now open, normally closed springs controlled by armature 222, lower winding of impulse repeating relay 205, armature 246, armature 236, resting contact of armature 243 and said armature, wiper 277, and through the upper winding of the line relay of the second selector to battery. Impulse repeating relay 205 at armature 234, therefore, interrupts the circuit extending to the second selec-tor a number of times corresponding to the number of times the line relay 202 of the selector repeater is deenergized. This repeating circuit is taken through the lower winding of impulse repeating relay 205 to compensate for the differences in line resistances or length of the trunk lines extending to the Various second selector accessible from this selector-repeater. The seized second selectoris, therefore, operated in the well known manner to extend the connection.

The impulses generated by armature 223 of line relay 202 to impulse conductor 308 are transmitted over the impulse wiper 314, conductor 318, series relay 356, rotary magnet 355, conductor 395, wiper 363 now in second position, and through the resistance 366 to battery. Series relay 356 at armature 357 again energizes the stepping magnet 368 to position the operating pawl to advance the wipers of the rotary control switch, from their second to their third position, while the rotar magnet 355 of the classiication switch C operates the wiper 358' in a rotary movement to engage with a contact jumpered in accordance with-the local zone metering arrangement. In this case it will be assumed that the wiper 358 has been operated vertically three steps and then rotated three steps to ground conductor 397 accessible to wiper 364 of the rotary. control switch RCS. When relay 356 deenergizes after this series of impulses stepping magnet 368 operates the wipers of the rotary control switch RCS from their second to their third position. When wiper 363 reaches its third position a circuit ma be traced from grounded interrupter IGy by way of armature 369 and its resting contact, upper winding of twostep relay 381, conductor 396, wiper 363, and through resistance 366 to battery. Two-step relay 381 is energized in its first step to close only armature 371 to prepare a circuit for operating the relay in its second step. When ground is removed from armature 369 by the rotation of the interrupter IG, ground by way of armature 375 and its working contact, armature, 371, the lower and upper windings of two-step relay in series now cause the two-step relay 381 to operate its armatures 370 and 369. At armature 369 the interrupter IG is disconnected from the relay 381 at its resting. contact and at its working contact prepares a circuit for intermittently operating relay 385. At armature 370 two-step relay 381 completes a locking circuit for itself extending by way of grounded armature 375, armature 371, lower and upper windings of relay 381, armature 370, and through resistance 366 to battery. Relay 385 is intermittently operated by the impulse interrupter IG and at armature 380 transmits impulses to the stepping magnet 368 of the rotary control switch to cause the rotary control switch to advance step-by-step until wiper 364 encounters a grounded contact. At armature 379 relay 385 also transmits impulses to the rotar magnet 284 of the class minor switch CM as follows: ground by way of armature 379, conductor 321, wiper 317, conductor 311, armature 276, and through the winding of rotary magnet 284 to battery. The wipers of the class minor switch CMS and the wipers of the rotary control switch RCS are, therefore, operated in unison until wiper 364 encounters the ground potential connected thereto by the operation of the classification switch wiper 358. In this case since the call was to the local or main zone the rotary control switch and the Class minor switch are advanced only one step because at this step wiper 364 closes the following circuit: ground by way of wiper 358, the thirty-third bank Contact in the classification switch bank, jumper extending to terminal switch 361, conductor 397, w1per 364, and through the winding of relay 382 to battery. Relay 382 energizes and at armature 373 completes a locking circuit for itself extending by way of either off-normal springs 362 of the rotary control switch RCS or by way of olf-normal springs 351 of classification switch CS. At armature 372 relay 382 opens the circuit extending through relays 383 and 384 with the result that relay 383 deenergizes. At armature 374 and its resting contact relay 383 completes an energizing circuit for release magnet 353 by way of vertical olf-normal springs 352 to cause the classification switch CS to release its wiper 358 to normal position, and at armature 375 and its working contact opens the lockin circuit of two-step relay 381 whereupon tie latter relay releases and at the resting contact of armature 375 closes a circuit for operating the stepping magnet 368 to cause the latter magnet to operate in a buzzer like manner to rotate the switch back to its normal position. The circuit for operating the stepping magnet 368 may be traced as follows: ground by way of armature 375 and its resting contact, conductor 390, multiple4 it will be remembered that it was assumedthat the call was from a subscriber who pays for all his calls on a metered basis and that the call just made was for'another subscriber in the same zone and that the rotary magnet 284 receives only one impulse to step the wipers of the class minor switch CMS l to their first position because relay 385 advanced the rotary control switch only one additional step when wiper 364 encountered the l ground potential determined by the setting of the classification switch wiper 358. The class minor switch remains in this position while the subscriber dials the remainder of the connection which is completed in a well known manner.

When the called subscriber answers, the connector reverses battery .in the well known manner thereby reversing the current flow in the upper winding of relay 211. Due to this reversal, the upper winding now 4assists the lower winding and relay 211 energizes. At armature 253 relay 211 closes an obvious circuit for energizing reversing relay 201 to reverse battery back to the calling subscriber for supervisory purposes and at armature 252 prepares for energizing relay 213.

Referring now to F 1g. 3 the impulse distributor ID constantly rotates in the direction as indicated by the arrow to cause the cam 344 to successively operate springs 345 to 350, inclusive, to close their contacts.

en springs 345 are closed by cam 344 conductor 337 is grounded to operate relay 322 and all other similar relays connected to com-v mon lead 337. At armature 329i and its working contact relay 322 grounds conductor 301 for the interval of time for which it is operated. In a like 327, inclusive, are operated to ground conductors 302 to 306, lnclusive. The impulse distributor ID rotates at a constant speed and thereforecauses conductors 301 to 306, inclusive, to be grounded in sequence at different predetermined time intervals.

manner relays 323 to(` From the above description it can be seen that only one relay, such as relays 322 to 327 ,l

inclusive, can be operated at the same time and, therefore,'only one of the conductors 301 to 306, inclusive, will be grounded at the same time. In case of a fault, however, if one of the conductors 301 to 306 is grounded a circuit may be traced from the grounded conductor through the terminatlng armature and its back contact to relay 328 and battery. In a like manner in case two or more of the conductors 301 to 306 become short-circuited due to a fault the operation of one of the relays completes an Venergizing circuit for alarm relay 328 from ground by way of the working contacts of the operated relay, one of the conductors and back through the other conductor which in this case is shorted, to the resting contact of an unoperated armature and through the upper winding of relay 328,

to battery. Atarmature 335 relay 328 closes a locking circuit for its lower winding; and at armature 336 closes a circuit for operating an alarm so that the attendant may clear the fault.v It will also be noted thatl this fault effects only the group of selector-repeaters which is individual to the conductors 301 to 306 and does not, therefore, effect the other groups in the exchange.

After the called subscriber has answered and when conductor 306 is grounded by the operation of relay 327 responsive to the operation of springs 350, a circuit may be traced for relay 213 as follows: grounded conductor 306, resting contact of armature 265 and said armature, lower winding of relay 213, armature 252, armature 266, wiper 280, and through the resistance to battery. Relay 213 energizes over the above traced circuit and at armature 258 completes an obvious locking circuit for itself through its upper winding. At armature 2,57 relay 213 prepares a circuit for operating the booster battery metering relay 213; at armature'259 relay 213 pre=- pares a circuit for energizing the rotary magnet 290 of thetime switch TS and at armature 260 prepares a circuit for connectin the 'warning time tone to the calling subscri ers line. A

Within a redetermined time interval after ground has een removed from conductor 306 by the rotation of the impulse distributor ID, cam 344 is operated to close springs 345 and operate relay to ground conductor 301. It will be remembered that the class 'minor switch CMS inthis call was rotated to Aarmature 231, armature 256, armature 261,

lower winding ot' two-step relay 214, and through resistance 291 to battery. Two-step relay 214 energizes and operates to close only its armature 262. At armature 254 booster battery meter relay 212 substitutes booster battery through resistance 255 for the ground connected to armature 227 and connects this booster battery potential byy way of release trunk conductor 26, through the line finder, to test wiper 23,test contact of the calling subscribers line, armature 15', conductor 9, and through the winding of marginal meter relay 32 to battery. Meter relay 32 will not energize when guarding ground is connected over conductor 9 but will energize as soon as meter-relay 212 energizes to connect booster battery potential thereto. At armatures 53.to 57, inclusive, meter relay 32 connects the meter leads 43 to 47, respectively, to the meter conductors connected to the meters terminating on the terminal stripV 59. It will be noted that grounded conductor 301 is also connected to conductor 43 and that, therefore, a circuit may be traced at this time for operating the local subscribers meter 31 as follows: from grounded conductor 301, conductor 43, armature 53, conductor 48, and through the winding of the local subscribers meter 31 to battery. The meter 31 is, therefore, operated one step responsive to the grounding of conductor 301 since at this time the class minor switch CMS is in its first position and the meter relays 32 and 212 are operated.

lVhen ground is removed from conductor 301 subscribers meter relay 32 and meter relay 212 deenergize and relay 212 at armature 256 removes the shunt circuit from around the upper winding of two-step relay 214, whereupon relay 214 operates in its second step due to the energization of its upper winding in series with its lower winding. At armature 261 two-step relay 214 opens a point in its original energizing circuit; at `armature 263 opens a point in the -circuit of meter rela 212; at armature 264 opens the locking clrcuit of relay 213; at armature 265 and its resting contact opens a point in the original energizing circuit of relay 213 and at its workin contact connects the impulse interrupter winding of relay 213 which, however, at this time is ineffective because armature 266 is now open and because the class minor switch has only been operated toits first position; at armature 267 'closes a circuit to the rotary magnet 290 of the time switch TS; and at armature 268 opens a point in the circuit to the release magnet 289 of the time switch TS. Relay 213 deenergizes and is unable to again energize because the class minor switch wiper is in position one and beoause armature 266 of relay 213 is operated. The calling subscribers meter 31 is, therefore, operated only once for this type of call since the time switch TS is not operated.

After the termination of the conversation and responsive to the calling subscriber replacing his receiver the circuit of line relay 202 is interrupted with the result that the line relay 202 deenergizes. Responsive to the deenergization of line relay 202 the circuit of release relay 204 is opened at armature 224 and the circuit of repeating relay 205 is opened at armature 223. Impulse repeating relay 205 at armature 234 opens the loop circuit extending back to the second selector to cause the second selector and the remaining switches in the switchl train to release in the well known manner. It will be understood, ofcourse, that the finder switching relay 215 releases' as soon as the classification switch CS and the rotary control switch RCS return to normal position and, therefore, remove v'round from the ground conductor 310. hortly after relay 205 deenergizes, the slowtorelease relay 204 deener izes and at armature 232 closes a circuit or operating both the release magnet 217 of the selector-repeater and the release magnet 283 of the class minor switch CMS over an obvious circuit. At armature 227 release rela 204 disconnects ground from release trun conductor 26 to permit the cut-oil relay 8 in the subscribers line circuit to deenergize and to render the calling line available for calls by way of the connector banks. In addition armature 227 opens the circuit of switching relay 206 which relay returns to its normal position. At armature 231 release relay 204 opens the locking circuit 'of two-step relay 214 with the result that this relay returns to its normal position to close the circuit to the release magnet 289 of the time switch TS. By the operation of the various release magnets, the selector repeater, the class minor switch CMS, and the classi- G to the lower IIJ `minor switch CMS and the rotar ication switch CS are returned to their normal Aposition and all of the relays in Fig. 2 are in normal position and the selector-repeater SR is again available for use on other calls.

At this time it should be |\pointed out that for the particular class of`\metered service under discussion there will be another meter connected to this subscribers meter leads 49 and 51 for metering calls to the north and south zones. It will nowbe assumed that calling subscriber S2 dials a number in the north zone instead of the local zone. The line finder, the selector-repeater, and the classification finder operate in the same manner as previously described. In this case since the call is to the north zone the impulses transmitted to the classification switch CS move the wiper 358 to ground a bank contact jumpered to conductor 392. It will be noted that this ground will extend from conductor 392 b wa of armature 378 of relay 384 to the fth ank contact accessible to wiper 364. The reason for extending the zone cross connections to contacts of relay 384 will be more fully described in connection with party line metering. After the rotary control switch RCS steps to third position, l.two-step relay 381 operates and completes the circuit for pulsing relay 385 and the latter relay pulses both the class control switch RCS as previously descri, d until wiper 364 encounters the cut-oil ground connected to its bank by the wiper 358 of the classification switch. The rotary control switch RCS, therefore, stops in position five when wiper 364 encounters a ground potential extending by way of conductor 392, armature 378 and conductor 389. "In this case the rotary magnet 284 of the class minor switch CMS have received two impulses by the operation of relay 385 and has, therefore, moved its wipers to their second positions in the same manner as previously described. The classiiication switch CS and the rotary control switch RCS are now released and are available for use in other calls.

When the called subscriber answers, a pulse on lead 306 will operate relay 213 and vwhen lead 302 is grounded by the impulse distributor ID and relay 323, relay 212 is energized to connect booster battery to the release trunk 26 to operate the meter relay 32. At the same time that relay 212 is energized, conductor 44, which is connected to conductor 302, is also grounded with the result that the meter connected to conductor 49 is operated. When the impulse distributor ID rotates cam 344 beyond springs 346 relay 323 deenergizes to remove ground from conductor 302 and conductor 44. Relays 212 and 32 thereupon deenergize and relay 214 operates in its second step. The operation u to this point is similar to that previously scribed but in this case, since wiper 280 of the class minor switch CMS is in its second position, a circuit may be traced through the lower windin of circuit 213 to the impulse interrupter I as follows: from ground by way of impulse interrupter IG, working contact .of armature 265 and said armature, lower winding of relay 213, armature 252, Second bank contact, wi per 280, and through the, resistance to battery. Impulse interrupter IG energzes relay 213 over the previously traced circuit every thirty seconds and since relay 214 is fully energized the locking circuit for relay 213 is not completed. Relay 213, therefore, transmits impulses by way of armature 259 and armature 267 to the rotary magnet 290 of the time switch TS. The time switch TS is, therefore, operated one step every thirty seconds. When wiper 285 of the time switch TS reaches its ninth position a warning tone will be connected by way of armature 260, wiper 285, and conductor 286 to the lower talking conductor to indicate to the calling subscriber that the live minute period is nearly up and that unless he hangs up within thirty seconds he will be metered for another period.

Assuming that the calling subscriber does not release the connection, another pulse will step the time minor switchTS to its tenth position.- When wiper 287 of the time switch TS reaches its tenth position a shunting ground circuit is connected around relay 214 upon the deenergization of relay 213 as follows: ground by way of armature 259 and its resting contact, tenth contact and wiper 287, through the lower and upper windings of relay 214, armature 262, to ground at armature 231. Two-step relay 214 thereupon deenergizes and at armature 268 completes the circuit for the release magnet 289 of the time switch TS to release the time switch to its normal position. At this point the relays and apparatus are in identical positions to those existing at the beginning of the callv when the called subscriber answered. Therefore, when conductor 306 is again grounded relay 213 is again gperated and when conductor 302 is again grounded meter relay 212 connects booster battery to the release trunk conductor 26 to operate the meter relay 32 and complete the circuit for voperating the subscribers meter 28 a second step for this call. From this point on the time switch again starts operating as previously described to -again operate the meter in case the subscriber maintains the connection.

In case the calling subscriber dials a number in the south zone the classification switch wiper 358 will be stepped to a point which in .turn is jumpered to conductor 293 and after the rotary control switch RCS reaches its third position relay 385 impulses both the class minor switch CMS and the rotary control Switch RCS until wiper 364 of the rotary control switch encounters the cut-off ground connected to conductor 393. In this case the class minor switch is stepped to its fourth position when Wiper 364 encounters the cut-oli' ground. lVhenthecalled subscriber answers, the same action just described will take' place as outlined for calls to the north zone with this except-ion, that the relay 32 and meter relay 212 are not operated except when the ground pulse appears on lead 304 by way of thc impulse distributor ID and meter impulse relays MIR. When ground is connected to lead 304 booster battery meter relay 212 connects booster battery to the release trunk to operate meter relay 32 and since con- (luctor 304 is connected to conductor 46 the operation of armature 56 of meter relay 32 connects this ground to the left-hand winding of meter 28 with the result that the meter is operated one step to charge for this call. The operation of the time switch TS and the release of the connection will be the same as l previously described.

From the above description it can readily be seen that the class ot' metered service as outlined under class B can easily be given by omitting the meter 31 connected to lead 48. and connecting a double wound meter to leads 49 and 51. In the case of service under.

wound meter to lead 49 and another-single wound meter to lead 51 in place of the double wound meter 28.

As previously stated, metered party line service is furnished with this equipment but in this case the party line subscribers are given class B service, that is, he pays a monthly rate snliicient to insure free calls into the main or local zone and pays for calls on the time basis to the north and south zones. In the case of calls from the first party on the party line, such as subscriber S, the operation of the equipment is identical to that described for single line subscribers having class 'B service.

The second partys telephone on a tele phone party line lis equipped with a dial which delivers a ground pulse to the line prior to the sending of the impulses for each digit. Referring now to Fig. 4, springs 1, 2, 3 and 4 are the shunt spring assembly of a calling device somewhat similar to the shunt spring assembly shown in Fig. 3 of Patent 1.642,822.v issued September 20, 1927, to H. F. bergfell. lVhen the calling device is moved olf-normal prior to sending the impulses, the cam 62 is rotated in the direction of the arrow and the insulated lug 61 which is secured to spring 3 slides in the rounded projection in cam 62 and permits all of the springs 1, 2,

-ground impulses are sent out before and after each digit has no particular significance because only the first ground pulse is utilized to produce th'e desired elect.

It will now be assumed that subscriber S initiates a call and responsive to the removal of the receiver the line relay 7 is energized over the sub'scribers loop to perform the same functions as described for relay 7 of the individual subscribers line. The line finder is initiated responsive to the operation of relay 7 to find the calling line and switch the same through to the selector-repeater SR. The line relay 202 and the release relay 204 operate in the same manner as previously described. The classification finder CSF is also operated to find an idle classification switch whereupon relay 215 is energized to transmit dial tone to the calling subscriber as previously described.

The functions just described are identical with the operations described vfor a single line subscriber, but n ow when the subscriber S operates his calling device to an off-normal position the shunt springs SS are opera-ted to ground conductors 5 and 6 whereupon the differential relay 203 in the selector-repeater is unbalanced with the result that the differential relay isv energized. Responsive to the energzation of the diierential relay 203 a circuit may now be traced for energizing relay 383 and marginal relay 384 as follows: from ground by way of armature 225, armature 271, conductor 309, wiper 31,5, conductor 319, armature 372, winding of relay 383, and through the lower winding of marginal relay 384 to battery. Since resistance 230 is excluded in the above traced circuit the marginal relay 384 is energized and locks itself energized over armatures 376 and 374. B v the operation of relay 384 it will be seen that the north and south zone. conductors 392 and 393 are transferred to different bank contacts in the bank accessible to wiper 364 in order to operate the proper party line subscribers vmeter, as will be more fullydescribed heresame 'setting of the class minor switch CMS. The booster battery meter relay 212 and the subscribers meter relay 30 are operated 111 the same manner as previously described but since no meter is connected to meter lead 33 the subscriber is not charged for calls into the local zone.

In case the subscriber S dials a number in the north zone the setting of the classification switch CS is the same as previously described and now since relay 384 is in operated position the rotary control switch RCS rotates wiper 364 to its sixth position in engagement with conductor 388 instead of 389 before the cut-ofi.l ground is encountered by said wiper. The class minor switch CMS is, therefore, operated to its third position with wiper 281 in engagement with the bank contact terminating conductors 45 and 303. When conductor 306 is grounded by the impulse distributor ID the relay 213 is energized to complete the relay operations previously set forth. When conductor 303 is grounded booster battery meter relay 212 energizes to connect booster battery to the release trunk conductor 26 to operate meter relay 30.' At the Sametime meter relay 30 is operated ground extending by way of conductor 303 and conductor 45, armature 40, and conductor 35 operates meter 29 individual to subscriber S. The o `eration'of the time switch and the release o the connection is the same as previously described for other calls to the north zone.

In case subscriber S dialledl a number in the south zone the classification switch CS would assume the setting assigned to Vthe south zone to ground conductor 393. Since relay 384 is now ener ized, grounded conductor 393 now exten s to the ei hth contact accessible to wiper 364 of t e rotary control switch RCS, with the result that Wiper 281 of the class minor switch CMS is operated in engagement with conductor 47 when the wiper 364 of the rotary control switch RCS encounters the cut-off ground as determined by the setting of the classification switch. After the called subscriber answers and when conductor 306 is grounded relay 213 is again energized and when the impulse distributor grounds conductor 305 meter relay 212 will connect booster battery to the release trunk conductor 26 to again operate the meter relay 30. Since conductor 305 is connected to conductor 47 the ground impulse connected to conductor 305 will now extend by way of conductor 47, armature 42, conductor 37 and through the left-hand winding of meter 29 to battery. Meter 29 is thereupon energized to operate the meter to charge for this call. The operationI of the time switch TS and the release of the connection is the same as previously described for a single subscriber on calls to the north zona 1,sss,sas

It will now be assumed that a calling subscriber commences to dial before di'al tone is received. As will be remembered the calling subscriber is not 'ven the dialtone until the classification fin er has found an idle vclassification switch which determines .the

typ; of metering to be ap lied to the callin su cribers line. The selector-repeater S is, therefore, arranged to be o erated vertically to the level dialled an then automatically rotated beyond the bank contact whereupon the callin subscriber is given a busy tone. In case t is conditionwas not provided for, a classification switch may be seized after a number of impulses of the first digit have been transmitted with the result that the classification switch CS would not be set in accordance with the complete digit dialled and, therefore, the metering would not be in accordance with the zone called. Under these conditions and responsive to the first impulse the vertical magnet 216 is operated to step the wiper one vertical step and to operate the selector-repeater vertical offnormal springs. At vertical off-normal springs 274 the original energizing circuit of the classification finder switching relay 215 is opened before this relay can energize and complete its locking circuit. switching relay 215 did not energize, the selector-re eater switching relay 206 is maintained sgunted over the following circuit: ground by way Ofarmature 269, armature 237, through the winding o-f switching relay 206 and to ground at armature 227. Responsive to the remaining impulses in the first digit the vertical magnet operates the wipers of the selector-repeater opposite the level dialled whereupon the rotary magnet is operated in the same manner as previously described to. rotate the wipers in Search of an idle second selector. However, since the selector-repeater switching relay 206 is shunted, the rotary magnet will continue to operate the wipers of the switch vuntil the wipers are rotated beyond the bank contact whereupon the cam springs 221 are operated to connect the busy tone tothe calling subscriber over the following circuit: from bus tone by wa of cam springs 221, vertical ofi? normal springs 226, through the lower windings of differential relay 203 and line relay 202, normally closed springs controlled by armature 220, normally closed springs controlled by armature 245, through the lower talking conductor 27 and over the calling subscribers loop. When the calling subscriber hears the well known busy tone he will replace his receiver and release the finder and selector repeater and will again call, this time waiting for dial tone.

In the case of special service calls to a special operator, which of course should not be metered against subscribers, the classification switch in conjunction with the selector Since finder Y w and 279 in order repeater is so arranged that metering will be prevented and the special servlce operator obtains a direct line to the subscriber with the first selector-repeater bridge removed. This type of service is required in conjunction with the present methods of handling toll calls on the so-c-alled CLR, or combined line and recording basis as well as for paystation service. When making a call to a special service operator the calling subscriber removes his receiver and Waits for dial tone. The line finder and the relays in the selectorrepeater are operated in the.l same manner as previously described and when the calling subscriber receives dial tone he will dial the number assigned to special service calls. Responsive to the digits dialled in the special service call the wiper 358 of the classification switch CS is operated to ground conductor 398 terminating in the ninth bank contact accessible to Wiper 364. Relay 385 therefore impulses the rotary control switch RCS and the class minor switch CMS until wiper 364 encounters this cut-off ground. The class minor switch CMS is, therefore, stopped in its sixth position with the result that the switch through relay 207 of the selector-repeater SR is operated from ground at armature 241 to battery connected to wiper 280. At armature 244 switching through relay 207 opens the circuit of the release relay 204 as well asv opening a point in the release circuits of the selector-repeater and the class minor switch release magnets. At armatures 243 and 245 relay 207 disconnects the selectorrepeater bridges and connects the conductors 25 and 27 direct through to the wipers 277 and 279, respectively. I-Iolding ground is now fed back over test wiper 278 for maintaining the switching relay 206 in energized position after the release relay 204 deenergizes and disconnects ground at armature 227 from the upper terminal of switching relay 206. The calling subscribers line is now extended direct to the operators position and the call from hereon is extended by the operator in the well known manner. After termination of the conversation, the holding ground is removed from switching relay 206 with the result that this relay and switching through relay 207 deenergize. By the deenergization of relay 207 armature 244 completes the circuits to the release magnets 217 and 283 to release the selector repeater and the class minor switch to their normal positions.

In the case of reverting calls on party lines, the code digits dialled are arranged to operate the classification switch CS and the cla-ss minor switch CMS so that the class minor switch CMS will be stopped in sixth position to operate the switching through relay 207 which relay energizes and connects the calling subscribers loop direct to the reverting call switches by way of wipers 277 to complete the reverting calls. In reverting calls the wiper 358 of the classification switch CS is therefore operated to a position to ground the ninth bank contact accessible to wiper 364 in order to set the class minor switch CMS in its sixth position.

In case of calls for the operator, it is customary to dial only one digit, that is, the digit O, This of course will not cause wiper 358 of the classification switch CS to step into the bank nor will it cause the control switch to go into third position because there is no second digit dialled. This condition is met by providing normal post springs which are operated when the classification switch wiper 358 is operated oppositethe O level of lthe classification switch bank. When wiper 358 is operated opposite the 0 level the normai post springs 359 operate to ground conductor 398 or the ninth position bank contact accessible to wiper 364 and at springs 360 connects ground to conductor 399 to energize the stepping magnet 368 to advance the wipers of the rotary control switch RCS when the magnet opens its interrupter springs367 and deenergizes as a result thereof. iVhen rotary control switch RCS reaches its third position two-step rela 381 is energized to complete the circuit or pulsing relay 385 and pulsing relay 385 operates both. the rotary control switch and the class minor switch in the same manner as previously described. In this case the class minor switch is stopped in its sixth position to energize the switching through relay 207 to connect the subscribers line direct to the operators position. It will be seen, therefore, that with the aid of the normal post springs NPS on the classification switch the same conditions are produced as those produced by dialling a special service digit code.

It will be noted that from the foregoing description that the metering scheme outlined herein does not only cover means for giving booster battery metering over the release trunk in conjunction with line finders but covers several metering features which are believed to be novel in view of the known zone and metering arrangement. As a matter of fact while zone and time metering are well known, it is believed that the introduction of a method wherebya subscriber can be given the choice of several classes of metered service is new. In addition, this method makes it possible to furnish two party metering service without vany special line equipment at the exchange.

Another feature which is obtained by the use of the classification switch is the ease with which circuit vconditions can be produced in the selector-repeater which will permit giving a combined line and recording and paystation service without the use of complicated intermediate repeater equipment. In addition it can be readily seen that not necessary to provide separate the jumfpering' arrangement between the banks o t rotary control switch can'be easily and readily Vchanged to produce an Y desired setting of service.

Having described the invention what is considered new Iand is desired to have rotected by Letters Patent will be set forth in the following claims:

What is claimed is:

1. In a measured service telephone system wherein a group of subscribers lines receive different classes of metered service, means for charging some of said lines for every completed connection, means for giving other of said 'lines free service-to local zones and for charging for every completed call to other zones, means forgiving the remaining lines in said group ree service to the local and a near zone and for charging for every completed call to other zones, and means common to said group of lines for controlling the charging means.-

2. In a measured service telephone system wherein a group of subscribers lines receive different classes of metered service, `a different number of meters individual to each line dependent upon the class of metered service each line receives, and means for operating a particular one `of the meters indivldual to a calling line inl response to the called party answering on a completed call to a called line, theparticular meter operated being dependent upon the location of the called line andfthe class of metered service said callin line receives.

3. n a measured service telephone system wherein a single group of subscribers lines receive different classesof metered service, there being both individual and party lines in said group, a different number of meters individual to each subscriber dependent upon the class of metered service each line receives, and means for operating a particular one of the meters individual to a calling subscriber dependent upon the location of the called line and the class of metered service said calling line receives.

4. In a measured service telephone system wherein a group of subscribers lines receive different classes of metered service, a meter relay for each line, means for operating thel meter relay of the calling line after a connection has been extended to a called line and the called party has answered, a different number of meters for each line, the number of'meters for each line being dependent upon the class of metered service each line he `classification switch and the receives, all the meters individual to the call ing line being prepared for operation responsive to the operation of said meter relay, and means for operating only a particular one of the meters of the calling line.

5. In a telephone system wherein a group of subscribers lines receive diterentclasses of metered service, a plurality of meter conone of said common meter conductors in ac! cordance with the location ofthe called line. and means for operating the meter relay of the calling line to connect corresponding meter leads to corresponding meter conductors after the called party answers to operate only the calling subscribers meter over the selected common conductor and corresponding meter lead in case a meter is connected to this individual lead.

6. In a measured service telephone system, rgroup of subscribers lines, a meter relay for each line, a plurality of meter conductors common to said group and connected to each meter relay, a different number of meters for each line dependent upon the class of metered service each line receives, means for extending a connection from a calling line in said group to a called line and for selecting a particular one of said conductors in accordance with the location of the called line, means controlled over said selected conductor for operating the meter relay of the calling line over said connection after the called party answers, means responsive -to the operation of said relay for connecting said common meter conductors to the meters of the calling line, and means for operating only the meter connected to said selected conductor.

7. In a measured service telephone system, a group of subscribers lines, a meter relay for each line, a variable number of meters for each line dependent upon the class of metered service each line receives, a plurality of individual meter leads for each line connected to its individual meter relay, each individual meter lead connected to a meter or not dependent upon the class of metered service each subscriber receives, a plurality of meter conductors common to said group and connected to each lmeter relay, means for extending a connection from a calling line in said group to a called line and for selecting a particular one of said common meter conductors in accordance with the location of the called line, means controlled over the selected conductor for operating the meter relay of the calling line over said connection after the called subscriber answers, means controlled by the operation of said meter relay for connecting each said individual meter lead to a corresponding one of said common meter conductors, and a circuit including said selected common conductor and its corresponding individual lead completed responsive to the operation of said relay for operating one of the subscribers meters in case a meter is connected to such individual meter lead.

8. ln a measured service telephone system, a calling subscribers line, a plurality of meters for said line, a plurality of meter conductors common to said line and other subscribers lines, a meter relay for said line having contacts for connecting each of said conductors to a meter of the calling line when operated, means for selecting a particular one of said conductors responsive to the extension of a connection from the calling line to a called line, means controlled over the selected conductor for operating said meter relay when the called party answers, and a circuit completed over said selected conductor for operating only one of said meters responsive to the operation of said meter relay.

9. ln a measured service telephone system., a group of subscribers lines, meters for said lines, a plurality of meter conductors common to said lines, means individual to each of said lines for connecting said meters to rsaid conductors, means for selecting a particular one oi said conductors responsive to the extension of a connection from a calling one of said lines to a called line` means for transmitting impulses to successive ones of said conductors at predetermined intervals, and means responsive to the called party answering for rendering the impulses transmitted to said selected conductor eiiective to operate the individual connecting means of the calling line and the calling subscribers meter.

10. In a measured service telephone system, a group oi subscribers lines, means for establishing a connection between a calling one and a called one of said lines, meter conductors common to said lines, a plurality o'f subscribers meters adapted to be connected to said conductors, means individual to each of said lines for connecting saidmeters to said conductors, and means common to said lines for operating the individual connecting means of a calling one of said lines responsive to the called party answering to operate only the calling subscribers meter over one of said conductors.

11. In a measured service telephone system, a calling line, a plurality of meters for said line, means for extending connections to called parties in local and distant zones,

means for selecting a particular one of said meters in case the called party is in the 1ocal zone or a different one of said meters in case the called party is in the distant zone to determine the charge to be assessed against the callingfsubscriber, and means operated by the response of the called parties for operating the selected meter to assess said charges.

12. ln a measured service telephone system, a calling line, a plurality of meters for said line, means for extending connections to called parties in local and distant zones, means for selecting a particular one of said meters in accordance with the location of the called parties to determine the charge to be assessed against the calling subscriber, means operated y y the response of the called parties for operating the selected meter to assc ss said charges, a time switch associated with said selecting means, and means for operating said time switch only on calls to distant zones to reoperate the selected meter at predetermined time intervals as long as the connection is maintained.

13. ln a measured service telephone system, a calling line, a plurality of meters for said line, a plurality of automatic switches accessible to said line and used in setting up connections to called parties in local and distant zones, means on the calling line for transmitting a plurality of series of impulses to operate said switches to extend a connection from the calling line to a called line, means responsive to the first and seco nd series of impulses for selecting a particular one of said meters in accordance with the location of the called line to determine the charge to be assessed against the calling subscriber, and means operated by the response of the called party for operating the selected meter to assesssaid charge.

14. In a measured service telephone system, a calling line, a plurality of meters .for said line, a plurality of automatic switches accessible to said line and used in sett-ing up connections to called parties in local and distant exchanges, zone metering equipment associa-ted with the first numerical switches in sald plurality of switches, means responsive to the initiation of a call by the calling line for seizing one of said rst numerical switches, means on the calling line for transmitting a plurality of series of impulses to operate some of said automatic switches to extend the connection to a called line, means responsive to the first and second series of impulses for setting said zone metering equipment to select one of said plurality of meters to determine the charge to be assessed against the calling subscriber, and means operated by the response of the called party for operating the selected meter to assess said charge.

15. In a measured service telephone system, a calling line, a plurality of meters for lsaid line, a plurality of automatic switches accessible to said line and used in setting up connections to called parties in local and distant exchanges, zone metering equipment associated with the first numerical switch in said plurality of switches, a zone classification switch temporarily associated with the first numerical switch when said first numerical switch is seized responsive to the initiation of a call on said calling line, means on the calling line for transmitting a plurality of series of impulses to said automatic switches to extend the connection to a called line, means responsive to the transmission of the first and second series of impulses for operating said zone classification switch to determine the char e to be assessed againstnsaid calling subscriber, meansw responsive to the operation of said zone classification switch for setting said zone metering equipment to select one of said meters inaccordance with the determined charge, and means operated A by the response of-the called party for operating the selected meter to assess said charge.

16. In a measured service telephone system, a r'oup of subscribers lines each having indiviual metering equipment, a group of automatic switches for use by this group of lines for extending connections to called subscribers lines, a group of meter conductors common to all said switches in the group and all said conductors normally connected to each individual metering equipment, means common -to the said group of lines and switches and other similar groups'of lines and switches for determining the metering operation to take place on completed connectic-ns to called lines, and means for controlling the operation of each individual metering equipment over said common conductors as determined by said common means after called subscribers answer in completed connections.

17. In a telephone system, a group of lines, a meter and a meter relay for each of said lines, a group oftrunk lines, a group of conductors common to said trunk lines and each conductor extending therefrom to each of said meter relays', means responsive to a call on one of said lines for taking one of said trunk lines into use to extend a connection toward a called line and for preparing a particular one of said common conductors for use dependent upon the location of the called s line, means in said trunk line controlled over said particular conductor for operating the calling lines meter relay after the called subscriber answers, and means for operating the calling subscribers-meter over said particular conductor responsive to the operation of said meter relay to charge for the call.

18. In a telephone system, a group of lines, a meter and a meter relay for each of said lines, a group of trunk lines, a group of conductors common to said trunk lines and each conductor extending therefrom to each oi said meter relays, means responsive to a call on one of said lines for taking one of said trunk lines into use to extend a connection toward a called line and for preparing a particular one of said common conductors for use dependentupon the location ofthe called line and means for controlling the operation of both the meter relay and the meter of the calling line over said particular conductor after the subscriber on the called line has answered t0 charge the calling subscriber for the call.

19. In a. measured service telephone sys- `te1n, a calling line, a meter relay and a meter therefor, a group of trunk lines, meter con` ductors common to said trunk lines and each conductor connected to said meter relay, means for extending a connection over one of said trunk lines and for selecting one of said conductors, means controlled over4 said selected conductor for operating the meter relay over said trunk line connection, and means responsive thereto for operating the meter over said selected conductor.

20. In a measured service telephone system, a group 'of subscribers lines, individual metering equipment for each of said lines, a group of trunk lines, a meter switch associated with each of said trunk lines, a group of relays common to said group of trunk lines, a group of conductors common to said group of trunk lines and s aid group .of subscribers? lines, said conductors extending from the banks of each of said meter switches to each individual metering equipment and to said group of relays, means for operating said relays to successively transmit grounded impulses to each of said conductors at predetermined timed intervals, means responsive to a call on one of said subscribers lines for taking one of said trunk lines into use and for operating the meter switch associated therewith to select one of said common conductors in accordance with the zone in which the called line is located, and means in said trunk line responsive to the called party answering for rendering the impulses transmitted by said relays effective to operate the calling subscribers metering equipment over the selected one of said common conductors.

21. In a telephone system, a group of calling lines, indivldual metering equipment for each of said lines, a group of trunk lines, a group of conductors common to said trunk lines and extending therefrom to each individual metering equipment, means responsive to a call on one of said subscribers lines for taking one of said trunk lines into use to extend a connection toward a called line and for preparing a articular one of said common conductors or use dependent upon the zone in which the called line is located, and means responsive to the called party answer- .ing for operating the calling subscribers meterin equipment jointly over saidtrunk line an over said repared conductor to charge the calling su scriber for the call.

22. In a measured service telephone system, three subscribers lines each having a Vdii'erent class of metered service, a different number of meters individual to each line dependent upon the class of service each line receives, a plurality of meter conductors, each of said conductors common to said lines, means for grounding said conductors in sequence at predetermined time intervals, means for selecting one of said conductors, means individual to each line for connecting said meters to di'erent ones of said conductors, and means for rendering only the ground impulses to said selected conductor effective' to operate the calling subscribers individual connecting means and a particular calling subscribers meter.

23. In a measured service telephone system, a group of subscribers lines having a iirst and a second party on each line, means for establishing a connection between a calling first party on one of said lines and a called line, a meter for each party on each of said lines, a meter relay for each of said lines, means common to said lines for selecting all the meters individual to each rst party in the group in response to the setting up of said connection, and means for operating the .meter relay associated with the calling line to operate only the said calling partys individual meter when the called party answers.

24. In a measured service telephone system, a group of subscribers lines having a Ifirst and a second party on each subscribers lines, a meter for each party on each of said lines, a meter relay for each of said lines, means for establishing a connection between a calling rst party on one of said lines and a called line, means common to said lines for selecting all the meters individual to each Virst party in the group in response to the setting up of said connection to a called line, means for operating the meter relay associated with the calling line to operate only the said calling partys individual meter when the called party answers, and means for repeating the operation of said meter relay and meter in case the connection is held for a predetermined length o time.

25. In a measured service telephone system, a oup of subscribers" lines having a first an a second party on each line, a plurality of meters individual to each party on said lines, trunk lines for use by this group of subscribers lines for extending connections 'to called subscribers lines, means in said trunk lines for determining which party on a calling line is calling, means common to said subscribers lines for selecting all the meters individual to all the first parties in the group in accordance With said determining means and for further selecting a particular one of said selected meters in accordance with the established connection to a called line, and means for operatin lthe particular selected meter when the calle party answers.

26. In a measured service telephone systcm, a group of subscribers lines including both individual and party lines, meters for the subscribers, a meter relay for each line, a

group of common meter conductors connectv the called line in case a second party on a.

party line is calling, and means for operating the meter relay of the calling line when the called party' answers to connect and operate the calling subscriber's meter over the selected conductor.

27 .In a measured service telephone system, a group of subscribers lines including both individual and party lines, meters for the subscribers, a meter relay for each line, a group of common meter conductors connected to each meter relay, a plurality of said conductors for use in'operating individual line meters and the first party meters on party lines, others of said conductors for use in operating the second party meters on party lines, means for connecting a calling line with a called line, means Jfor selecting one of said plurality of conductors in accordance With the location of the called line in case an individual line or a irst party on a party line is calling and for selecting one of said other conductors in accordance with the location of the called line in case a second party on a party line is calling, means for transmitting ground impulses to successive ones of said conductors at predetermined intervals, said impulses normally ineffective, and means responsive to the called party answering for rendering the impulses transmitted to said selected conductor eli'ective to operate both the meter relay of the calling line and the calling subscribers meter.

28. In a measured service telephone system, a group of subscribers lines, meters for said lines, a meter relay for each line, a plurality of common meter conductors connected to each meter relay, means for successively connecting ground impulses to successive ones of said conductors at predetermined intervals, means or connecting a calling line with a called line, means for selecting one of said conductors in accordance with the location of a called line re- 

